Single pivot elevator mounting for self-loading scrapers



23, 1969 L. e. EFTEFIELD ET AL 3,423,853 v SINGLE PIVOT ELEVATOR MOUNTING FOR SELF-LOADING SCRAPERS Filed Aug. 1, 1966 r 7 Sheet Y R R A .L

, 2.," 4P ATTORNEYS Jan. 28, 1969 SINGLE PIVOT u.. e. EFTEFIELD ET AL 3,423,853

ELEVATOR MOUNTING FOR SELF-LOADING SCRAI ERS Filed Aug. 1, 1966 Sheet 2 of 5 INVENTORS. LARRY CT, EFTEF'lELD R\C.HARD K. mass LAWRENCE J'. M\LLE.R ERNEST W. WAGNER Jan. 28, 1969 'L. e. EFTEFIELD ET AL 3,423,853

SINGLE PIVOT ELEVATOR MOUNTING FOR SELF-LOAISING SCRAPERS v R M m m m rm E 5 W U w w 3 I I QM/ A Sheet N") LO LARRY G. EFTEHELD R\C.HARD K LAWRLNCE J. MULLER ERmasT W Filed Aug. 1. 1966 United States Patent Claims Int. Cl. E02f 3/76 ABSTRACT OF THE DISCLOSURE The elevator of a simplified self-loading scraper is coupled to the scraper body by a single pair of pivot arms whereby the elevator may adjust to varying depth of cut by pivoting about a single horizontal axis. The forward ends of the arms connect to the elevator through hinge joints which are rigid with respect to pivoting in 'a vertical plane while providing lateral flexibility. Downward movement of the elevator is limited by horizontal tracks on the bowl sidewalls which are contacted by rollers on the sides of the elevator. The rearward ends of the arms couple to the scraper ejector mechanism through ball and socket joints whereby the elevator is shiftedforward by operation of the ejector.

This invention relates to tractor drawn earthmoving equipment and more particularly to support structure for the elevator of a self-loading scraper.

Substantial operating economies are realized in the loading of tractor drawn scrapers through the use of an elevator thereon which extends upwardly from the cutting blade at the front end of the load carrying bowl. The elevator aids the movement of freshly cut soil from the blade into the bowl. This reduces the resistance which the load exerts against the entrance of additional soil into the bowl and usually avoids any need for using an additional pusher tractor to complete loading of the scraper with its attendant cost, manpower and scheduling complications.

In order that the elevator may override obstacles, such as large stones and the like, and to allow the elevator to adjust itself to varying loading and varying depths of cut, it is customary to provide some form of floating mounting. The mounting structure must allow the lower end of the elevator to pivot upwardly when necessary while providing sufficient holddown force to avoid excessive jumping and loss of elevator action. This movement must take place in a way which will not cause interference with other mechanisms of the scraper. Further, the floating elevator must function to retain the load in the bowl at the front end thereof.

In order to meet these various requirements, floating elevator mountings have tended to be unduly complex with consequent high costs and maintenance problems. Such mountings have typically required four pivot arms between the corners of the elevator frame and the scraper body with stops for limiting pivoting motion and, in some cases, with springs for providing holddown force. In such a structure there are in effect four separate axes about which pivoting movement may occur.

In addition to undue complexity, and partly as a result thereof, such elevator mountings have lacked features that would be highly desirable. Prior mountings have not, for example, been susceptible to easy disconnection of the elevator from the mounting. This is a highly desirable characteristic in that it makes it practical to separate the elevator from the scraper body to facilitate transporting the scraper. By separating the elevator in this manner, the center of gravity of the scraper is lowered making it a 3,423,853 Patented Jan. 28, 1969 "ice more stable load. Further, problems with overhead clearances are reduced.

Difliculties have also been experienced with prior forms of elevator mounting in the course of ejecting the load in that the contents of the bowl tend to be wedged against the elevator by movement of the ejecting elements of the scraper. Copending application Ser. No. 563,403, entitled Self-Loading Scraper Elevator Mounting, and filed July 7, 1966, by Trevor G. Campbell, Robert W. Lichti, and Richard K. Liess, describes and claims means for alleviating this problem by linking the elevator to the ejection mechanism so that the elevator is shifted during ejection to avoid wedging. It is highly desirable that any simplified elevator mounting be adaptable to the inclusion of this feature.

The present invention is an elevator mounting which meets the several requirements discussed above while requiring fewer pivot arms and requiring only a single pivot axis.

Accordingly it is an object of this invention to provide a simplified elevator mounting structure for a self-loading earthmoving scraper having the desirable characteristics of more complex structures.

It is an object of the invention to provide a floating elevator mounting for a self-loading scraper which requires a minimum number of pivot arms and only a single horizontal pivot axis.

It is another object of this invention to provide a floating elevator mounting for a scraper from which the elevator may be disengaged conveniently.

It is still another object of the invention to provide a simplified pivoting elevator mounted for a scraper in which the elevator is shifted during load ejection to avoid wedging of the contents of the scraper against the elevator.

The invention, together with further objects and advantages thereof, will best be understood by reference to the following specification taken together with the accompanying drawings, of which:

FIG. 1 is a side elevation view, partially in section, of a tractor drawn self-loading scraper utilizing the invention.

FIG. 2 is a side elevation view, partially in section, of a portion of the scraper of FIG. 1 and illustrating the pivoting movement of the elevator and associated structure thereof.

FIG. 3 is a foreshortened plan section view taken along line IIIIII of FIG. 2 illustrating details of the elevator mounting structure.

FIG. 4 is a section view of a hinge connection which attaches the elevator to the mounting structure, taken along line IV-IV of FIG. 3.

Referring now to the drawing and particularly to FIG. 1 thereof, the scraper 11 has a load carrying bowl assembly 12 with an earth cutting blade 13 projecting downwardly and forward from the front end for cutting a layer of the underlying soil 14 which passes over the blade and up a sloping blade support 16 into the bowl. Bowl assembly 12, which has sidewalls 17 and an arcuate rearwall 18, is supported at the rearward end by a frame 19 and a pair of rear wheels 20 which establish a pivot axis about which the bowl may be raised or lowered to adjust the depth of cut of blade 13.

A two wheel tractor 21 draws the scraper through a swivel 22, gooseneck 23, transverse spreader 24 and a pair of draft arms 26 which extend rearwardly from the ends of the spreader and are coupled to the bowl sidewalls 17 by pivots 27. To adjust the vertical position of the cutting blade 13 and bowl 12, a pair of hydraulic jacks 28 are connected between the spreader 24 and the frame 19 at the front of the bowl.

To provide for ejection of the load, the floor of bowl 12 is formed by a pivoting platform 29 which in its lower position bridges the gap between the cutting blade support 16 and the bottom edge of the bowl rearwall 18. Triangular side members 31 on platform 29 extend upward within the bowl 12 to couple the platform to the bowl sidewalls 17 at pivots 32 which are at the center of curvature of the rearwall 18. Platform 29 may thus swing upwardly and rearwardly to release the contents of the bowl through the bottom thereof. To operate the ejection mechanism, a lever 33 is pivoted to frame 19 behind bowl 12 and has a lower end angled forwardly under the bowl and pivotably connected to a straight link 34. The forward end of link 34 is pivoted to the underside of the forward portion of platform 29. A hydraulic jack 36, controlled from the operators compartment of tractor 21, is connected between an intermediate point on lever 33 and frame 19 to effect the above described pivoting movement of the platform 29.

Self-loading scrapers of this class are provided with an elevator structure 37 which extends from the cutting blade 13 upwardly and back at the front of the bowl 12. Elevator 37 assists the movement of soil from blade 13 up into bowl 12 and further functions to retain the load in the bowl at the front end thereof.

Elevator 37 will typically have a rectangular frame 38 with a first pair of sprocket wheels 39 at the upper corners thereof and a second pair of sprockets 41 at the lower end. Endless chains 42 are carried by the sprocket wheels 39 and 41 at each side of frame 38 and are interconnected at spaced intervals by flights 43 which function to move the soil. Idler wheels 44 are mounted on the frame 38 to support the chains 42 between sprockets 39 and 41 and the upper sprockets 39 are driven by means such as a hydraulic motor 46.

Considering now the mounting structure which enables the elevator 37 to override obstacles and to adjust to varying depths of cut and which provides the several other advantages hereinbefore discussed, a pair of pivot arms 47 extend back from the central portion of the elevator, one at each side thereof, and constitute the sole means by which the elevator is coupled to the scraper.

Although the arms 47 may be linear, greater strength and rigidity is obtained by branching the forward end of each arm with a first branch 48 being coupled to the elevator frame 38 below the center thereof, by a hinge connection 49, and with the second branch 51 extending upwardly to connect with the elevator frame at hinge connections 52 situated above the center thereof. The rearward portion of each arm 47 connects, by means of a pivotable ball and socket joint 53, with an upwardly projecting finger 54 of the platform side-member 31 at the corresponding side of the scraper. The ball and socket joints 53 are preferable to other pivotable couplings in that such joints allow some lateral self-adjustment of the structure.

The pivot axis of joints 53 is located above the axis of the pivots 32 about which the bowl platform 29 turns. Thus, as shown in FIG. 2, pivoting of the platform 29 to the open position for ejecting the load from bowl 12 simultaneously shifts the elevator 37 forwardly. As described in the hereinbefore identified copending application, such forward movement of the elevator 37 alleviates the tendency of the load to wedge against the elevator during ejection.

To avoid impact of the elevator flights 43 against the cutting blade 13, means are required for limiting the extent to which the elevator can pivot downward. Referring now to FIGS. 2 and 3 in conjunction, a horizontal track 56 with a linear groove 57 therein is formed in each bowl sidewall 17 immediately below the upper elevator hinge connections 52. An arm 58 projects laterally from the elevator frame 38 at each side thereof and roller wheels 59 mounted on the ends of the arms ride upon the tracks 56. To limit sideward shifting of the elevator 37, each such roller 59 has a central flange 61 extending into the groove 57 of the track 56. Sideward movement of the support structure is further limited by abutment plates 62 on the sides of the elevator pivot arms 47.

Referring now to FIGS. 3 and 4 in conjunction, the hinge connections, such as hinge 52, which couple the elevator 37 to the pivot arms 47 are arranged to facilitate assembly and disassembly of the elevator. Hinge 52 is formed by a first set of annuli 64 formed on roller arm 58 which interleave coaxially with a second set of such annuli 66 on the end of pivot arm 47. A hinge pin 67 extends through the annuli 64 and 66 and is held in place by retainer rings 68 secured to each end of the pin by transverse bolts 69. The axis of the pin 67 and annuli 64 and 66 is parallel to the side of elevator frame 38 so that the hinges 52 allow some sideward self-adjustment of the structure while being in effect a rigid connection insofar as the pivoting movement of the elevator 37 about the hinges in a vertical plane is concerned.

The above described structure provides for easy detachment of elevator 37 from the scraper 11 for storage or transportation. Ball and socket joints 53 may be disengaged and, if chains 42 are removed, pivot arms 47 may be swung towards the elevator frame.

What is claimed is:

1. In a tractor-drawn self-loading scraper of the class having a body with a load carrying bowl and with a cutting blade projecting downwardly and forwardly from the front end thereof and having a floating elevator extending upwardly from said blade at the front end of said bowl, a mounting structure for said elevator comprising at least one pivot arm extending rearwardly from said elevator to said scraper body, a first coupling connecting said elevator to the forward end of said arm rigidly with respect to pivoting of said elevator about said forward end of said arm in a vertical plane, said first coupling being a hinge joint with a pivot axis substantially parallel to the sides of said elevator whereby said first coupling provides for pivoting of said elevator relative to said arm about an axis parallel to the sides of said elevator, a second coupling connecting the rearward end of said arm to said scraper body for pivoting in a vertical plane, and a stop limiting downward pivoting of said arm and said elevator about said second coupling.

2. In a tractor-drawn self-loading scraper of the class having a body with a load carrying bowl and with a cutting blade projecting downwardly and forwardly from the front end thereof and having a floating elevator extending upwardly from said blade at the front end of said bowl, a mounting structure for said elevator comprising at least one pivot arm extending rearwardly from said elevator to said scraper body, a first coupling connecting said elevator to the forward end of said arm with respect to pivoting of said elevator about said forward end of said arm in a vertical plane, said first coupling being disengageable, wherein said first coupling is a hinge having a first member secured to said arm and a second member secured to said elevator, said first and second members being coupled by a readily removable hinge pin extending through each thereof, said hinge pin being directed parallel to the sides of said elevator, a second coupling connecting the rearward end of said arm to said scraper body for pivoting in a vertical plane, and a stop limiting downward pivoting of said arm and said elevator about said second coupling.

3. In a tractor-drawn self-loading scraper of the class having a body with a load carrying bowl and with a cutting blade projecting downwardly and forwardly from the front end thereof and having a floating elevator extending up wardly from said blade at the front end of said bowl, and wherein said bowl has a base which pivots rearwardly to discharge the contents of said bowl through the bottom thereof, said base having side members which extend up above the level of the pivot axis thereof, a mounting structure for said elevator comprising a pair of pivot arms extending rearwardly from said elevator to said scraper body with one arm being at each side of said elevator,

5. a pair of first couplings each connecting said elevator to the forward end of a separate one of said arms rigidly with respect to pivoting of said elevator about said forward end of said arm in a vertical plane, said first couplings being disengageable, a pair of second couplings each connecting the rearward end of one of said arms to the corresponding one of said side members above the level of the pivot axis of said base whereby said elevator is pivotable in a vertical plane and is shifted forwardly upon rearward pivoting of said base and a pair of stops limiting downward pivoting of said arms and said elevator about said second couplings.

4. Mounting structure for the elevator of a self-loading scraper as defined in claim 3 wherein said stop comprises a substantially horizontal track on said scraper body and a wheel mounted on said elevator and contacting said track at the lowermost position of said elevator whereby said elevator is shifted substantially forwardly upon rearward pivoting of said base.

5. In a tractor-drawn self-loading scraper of the class having a body with a load carrying bowl and with a cutting blade projecting downwardly and forwardly from the front end thereof and having a floating elevator extending upwardly from said blade at the front end of said bowl, a mounting structure for said elevator comprising at least one pivot arm extending rearwardly from said elevator to said scraper body, a first coupling connecting said elevator to the forward end of said arm rigidly with respect to pivoting of said elevator about said forward end of said arm in a vertical plane, said first coupling being disengageable, a second coupling connecting the rearward end of said arm to said scraper body for pivoting in a vertical plane, wherein said second coupling is a ball and socket joint allowing said arm and said elevator a limited degree of lateral self-adjustment, and a stop limiting downward pivoting of said arm and said elevator about said second coupling.

References Cited UNITED STATES PATENTS 3,090,139 5/1963 Hancock 378 3,334,428 8/1967 Rezabek 378 2,994,976 8/1961 Hancock 378 ROBERT E. PULFREY, Primary Examiner. E. E. EICKHOLT, Assistant Examiner.

US. Cl. X.R. 

